U.S. patent application number 15/781807 was filed with the patent office on 2020-08-27 for distributed drivetrain architectures for commercial vehicles with a hybrid electric powertrain and dual range disconnect axles.
This patent application is currently assigned to DANA HEAVY VEHICLE SYSTEMS GROUP, LLC. The applicant listed for this patent is DANA HEAVY VEHICLE SYSTEMS GROUP, LLC. Invention is credited to RAYMOND J. HAKA, KRISHNA KUMAR, STEVEN J. WESOLOWSKI, JAMES F. ZIECH.
Application Number | 20200269675 15/781807 |
Document ID | / |
Family ID | 1000004827034 |
Filed Date | 2020-08-27 |
United States Patent
Application |
20200269675 |
Kind Code |
A1 |
HAKA; RAYMOND J. ; et
al. |
August 27, 2020 |
DISTRIBUTED DRIVETRAIN ARCHITECTURES FOR COMMERCIAL VEHICLES WITH A
HYBRID ELECTRIC POWERTRAIN AND DUAL RANGE DISCONNECT AXLES
Abstract
A hybrid drivetrain is provided. The hybrid drivetrain comprises
a power source, a transmission, and a tandem axle assembly. The
transmission includes a primary clutch and is drivingly engaged
with the power source. The tandem axle assembly includes a first
axle and a second axle and is drivingly engaged with the
transmission. One of the transmission and the tandem axle assembly
includes a first motor generator in electrical communication with a
battery. The first motor generator and the primary clutch
facilitate operating the hybrid drivetrain as a hybrid drivetrain
in a plurality of operating modes. The hybrid drivetrain may
further comprise second and third motor generators in electrical
communication with the battery to facilitate operating the hybrid
drivetrain in a plurality of operating modes.
Inventors: |
HAKA; RAYMOND J.; (BRIGHTON,
MI) ; KUMAR; KRISHNA; (HOLLAND, OH) ;
WESOLOWSKI; STEVEN J.; (WATERVILLE, OH) ; ZIECH;
JAMES F.; (KALAMAZOO, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DANA HEAVY VEHICLE SYSTEMS GROUP, LLC |
MAUMEE |
OH |
US |
|
|
Assignee: |
DANA HEAVY VEHICLE SYSTEMS GROUP,
LLC
MAUMEE
OH
|
Family ID: |
1000004827034 |
Appl. No.: |
15/781807 |
Filed: |
December 7, 2016 |
PCT Filed: |
December 7, 2016 |
PCT NO: |
PCT/US2016/065285 |
371 Date: |
June 6, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62264089 |
Dec 7, 2015 |
|
|
|
62406126 |
Oct 10, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60K 6/442 20130101;
B60K 17/36 20130101; B60K 6/445 20130101; B60Y 2400/73 20130101;
B60K 6/387 20130101; B60K 17/165 20130101; B60K 6/547 20130101;
B60Y 2200/92 20130101 |
International
Class: |
B60K 6/442 20060101
B60K006/442; B60K 17/16 20060101 B60K017/16; B60K 17/36 20060101
B60K017/36; B60K 6/387 20060101 B60K006/387; B60K 6/445 20060101
B60K006/445; B60K 6/547 20060101 B60K006/547 |
Claims
1-18. (canceled)
19. A hybrid drivetrain, comprising: a power source; a transmission
including a primary clutch, the transmission drivingly engaged with
the power source through the primary clutch; and a tandem axle
assembly including a first axle and a second axle, the tandem axle
assembly drivingly engaged with the transmission, wherein the
transmission comprises a first planetary gearset comprised of a
carrier portion, a sun gear portion and a ring gear portion all
drivingly connected, wherein the carrier portion is connected to
the primary clutch, wherein the ring gear portion is connected to a
first motor generator, a gear box and then the tandem axle
assembly, wherein the sun gear portion is connected to a second
motor generator, wherein the first and second motor generators and
the primary clutch facilitate operating the hybrid drivetrain as a
hybrid drivetrain in more than one operating modes.
20. The hybrid drivetrain according to claim 19, further comprising
a secondary clutch between the first motor generator and the gear
box portion.
21. The hybrid drivetrain according to claim 19, wherein a battery
and a controller are connected to the first and second motor
generators.
22. The hybrid drivetrain according to claim 21, wherein one of the
transmission and the tandem axle assembly further comprises a third
motor generator in electrical communication with the battery.
23. The hybrid drivetrain according to claim 19, wherein the tandem
axle assembly further comprises a selection clutch connected to the
gearbox.
24. The hybrid drivetrain according to claim 23, wherein the tandem
axle assembly has a electric axle drive unit with a second
planetary gearset located before the selection clutch.
25. The hybrid drivetrain according to claim 19, wherein a portion
of the primary clutch is an input for the transmission and a
portion of the gear box is an output for the transmission.
26. The hybrid drivetrain according to claim 19, wherein the
primary clutch, the first motor generator and the second motor
generator are in driving engagement with portions of the first
planetary gearset.
27. The hybrid drivetrain according to claim 19, wherein the
secondary clutch is in driving engagement with the first motor
generator and the gear box.
28. The hybrid drivetrain according to claim 19, wherein tandem
axle has a first mode of operation where both the first and second
axles are driven.
29. The hybrid drivetrain according to claim 19, wherein the tandem
axle has a second mode of operation where only a single axle is
driven.
30. The hybrid drivetrain according to claim 19, wherein the first
and second motor generators selectively directly drive in series
the tandem axle.
31. The hybrid drivetrain according to claim 19, wherein the third
motor generator is in parallel with the first and second motor
generators to selectively directly drive the tandem axle.
32. The hybrid drivetrain according to claim 19, wherein the ring
gear portion is connected to the first motor generator, the gear
box and then the tandem axle assembly through the second motor
generator.
Description
CLAIM OF PRIORITY
[0001] The present application claims the benefit of priority to
U.S. Provisional Application No. 62/264,089 filed on Dec. 7, 2015
and U.S. Provisional Application No. 62/406,126 filed on Oct. 10,
2016, which are incorporated herein in their entirety by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to drivetrains for commercial
vehicles and more particularly to hybrid electric drivetrains for
commercial vehicles.
BACKGROUND OF THE INVENTION
[0003] Commercial vehicles or trailers having two or more rear
axles allow such vehicles to carry greater loads when compared to
vehicles and trailers having a single axle. Further, tractive
effort and load distribution can be increased in these
vehicles.
[0004] Hybrid powertrains incorporate a second power source, such
as a motor-generator and a battery, that can be used to increase an
efficiency of a drivetrain. Currently, few options for hybridized
drivetrains for commercial vehicles are available. Because of the
unique demands of commercial vehicles, such as the need for a low
speed, high torque mode of operation while also having a high
speed, low torque mode of operation, many challenges exist in
successfully implementing a hybridized drivetrain for use with
commercial vehicles. Further, regulations posed by governments
increasingly demand fuel efficiency improvements for such
vehicles.
[0005] It would be advantageous to develop a hybridized drivetrain
for commercial vehicles that meets the exacting needs of commercial
vehicles while providing fuel efficiency improvements for vehicles
incorporating the hybridized drivetrain.
SUMMARY OF THE INVENTION
[0006] Presently provided by the invention, a hybridized drivetrain
for commercial vehicles that meets the exacting needs of commercial
vehicles while providing fuel efficiency improvements for vehicles
incorporating the hybridized drivetrain, has surprisingly been
discovered.
[0007] In one embodiment, the present invention is directed to a
hybrid drivetrain. The hybrid drivetrain comprises a power source,
a transmission, and a tandem axle assembly. The transmission
includes a primary clutch and is drivingly engaged with the power
source. The tandem axle assembly includes a first axle and a second
axle and is drivingly engaged with the transmission. One of the
transmission and the tandem axle assembly includes a first motor
generator in electrical communication with a battery. The first
motor generator and the primary clutch facilitate operating the
hybrid drivetrain as a hybrid drivetrain in a plurality of
operating modes.
[0008] Various aspects of this invention will become apparent to
those skilled in the art from the following detailed description of
the preferred embodiment, when read in light of the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The above, as well as other advantages of the present
invention, will become readily apparent to those skilled in the art
from the following detailed description when considered in the
light of the accompanying drawings in which:
[0010] FIG. 1 is a schematic style view of a hybrid drivetrain
according to a first embodiment of the invention;
[0011] FIG. 2 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention;
[0012] FIG. 3 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention;
[0013] FIG. 4 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention;
[0014] FIG. 5 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention;
[0015] FIG. 6 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention;
[0016] FIG. 7 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention;
[0017] FIG. 8 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention;
[0018] FIG. 9 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention; and
[0019] FIG. 10 is a schematic style view of a hybrid drivetrain
according to another embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] It is to be understood that the invention may assume various
alternative orientations and step sequences, except where expressly
specified to the contrary. It is also to be understood that the
specific devices and processes illustrated in the attached
drawings, and described in the following specification are simply
exemplary embodiments of the inventive concepts of the present
invention. Hence, specific dimensions, directions, orientations or
other physical characteristics relating to the embodiments
disclosed are not to be considered as limiting, unless expressly
stated otherwise.
[0021] FIG. 1 is a schematic style view of a hybrid drivetrain 100
according to a first embodiment of the invention. The hybrid
drivetrain 100 includes a power source 102, a hybrid transmission
104, and a tandem axle drive unit 106, the tandem drive axle unit
106 including a first axle drive unit 144 and a second axle drive
unit 146. The power source 102 is drivingly engaged with an input
of the hybrid transmission 104. The tandem axle drive unit 106 is
drivingly engaged with an output of the hybrid transmission
104.
[0022] The power source 102 is an internal combustion engine,
however, it is understood that the power source 102 may also be a
hybrid type power source incorporating a secondary power source in
addition to an internal combustion engine. Further, it is
understood that the power source 102 may also be a source of
electrical power, such as a fuel cell.
[0023] The hybrid transmission 104 includes a primary clutch 108, a
planetary gearset 110, a first motor-generator 112, a second
motor-generator 114, a secondary clutch 116, and a gear box 118. A
portion of the primary clutch 108 acts as the input for the hybrid
transmission 104. A portion of the gear box 118 acts as the output
for the hybrid transmission 104. The primary clutch 108, the first
motor-generator 112, and second motor-generator 114 are in driving
engagement with portions of the planetary gearset 110. The
secondary clutch 116 is in driving engagement with the first
motor-generator 112 and the gear box 118.
[0024] The primary clutch 108 is a clutch which can be variably
engaged, such as a plate or cone style clutch.
[0025] The planetary gearset 110 comprises a sun gear portion 120,
a carrier portion 122, and a ring gear portion 124. The sun gear
portion 120 is in driving engagement with the second
motor-generator 114. The carrier portion 122 is in driving
engagement with a portion of the primary clutch 108. The ring gear
portion 124 is in driving engagement with the first motor-generator
112. It is understood that the planetary gearset 110 may have other
configurations that facilitate a similar operation; in which
torques applied by the power source 102 and the second motor
generator 114 may be summed and applied to the first motor
generator 112.
[0026] The first motor generator 112 is in driving engagement with
the ring gear portion 124 of the planetary gearset 110 and the
secondary clutch 116. The first motor generator 112 is in
electrical communication with a controller 126 and a battery 128.
It is understood that the first motor generator 112, or any of the
other motor generators described herein, may be incorporated into a
gearbox, transmission, or other driveline component of the hybrid
drivetrain 100. Depending on an electrical control of the first
motor generator 112 using the controller 126, the first motor
generator 112 may apply a driving force to propel or retard a
portion of the hybrid drivetrain 100 it is drivingly engaged
with.
[0027] The second motor generator 114 is in driving engagement with
the sun gear portion 120 of the planetary gearset 110 and the
secondary clutch 116. The second motor generator 114 is in
electrical communication with the controller 126 and the battery
128. It is understood that the second motor generator 114, or any
of the other motor generators described herein, may be incorporated
into a gearbox, transmission, or other driveline component of the
hybrid drivetrain 100. Depending on an electrical control of the
second motor generator 114 using the controller 126, the first
motor generator 112 may apply a driving force to propel or retard a
portion of the hybrid drivetrain 100 it is drivingly engaged
with.
[0028] The secondary clutch 116 is a clutch which can be variably
engaged, such as a plate or cone style clutch.
[0029] The gear box 118 is a multi-speed gearbox in driving
engagement with the secondary clutch 116 and the tandem axle drive
unit 106. The gear box 118 may be manually or automatically
operated.
[0030] The tandem axle drive unit 106 is drivingly engaged with the
gear box 118, a first axle 130, and a second axle 132. The tandem
axle drive unit 106 is configured to be placed in two modes of
operation, depending on a position of a selection clutch 134. In a
first mode of operation, the tandem axle drive unit 106 operates in
a high torque, dual axle mode operation. In a second mode of
operation, the tandem axle drive unit 106 operates in a low torque,
single axle mode operation. As shown in FIG. 1, the hybrid
driveline 100 includes an optional axle disconnect clutch 136. The
tandem axle drive unit 106 is similar in structure and
functionality to the planetary drive unit 716 shown in FIG. 7,
described hereinbelow.
[0031] In use, through control of the primary clutch 108 and the
secondary clutch 116, driving and charging can occur with and
without engagement with the rest of the hybrid drivetrain 100. The
hybrid drivetrain 100 is a series-parallel hybrid drivetrain, and
may be operated in a plurality of operating modes as described
hereinbelow. The first motor generator 112 is placed inline in the
hybrid drivetrain 100, and the second motor generator 114 can be
used to supplement the hybrid drivetrain 100 through the planetary
gearset 110. The motor generators 112, 114 provide the following
benefits: engine downsizing, efficiency improvement by operating
the power source 102 within a narrower band (allowing the second
motor generator 114 to provide acceleration flexibility), reduced
gearing in the gearbox 118, and a downsizing of the axles 130,
132.
[0032] FIG. 2 is a schematic style view of a hybrid drivetrain 200
according to another embodiment of the invention. The hybrid
drivetrain 200 includes a power source 202, a hybrid transmission
204, and a tandem axle drive unit 206, the tandem axle drive unit
206 including a first axle drive unit 244 and a second axle drive
unit 246. The power source 202 is drivingly engaged with an input
of the hybrid transmission 204. The tandem axle drive unit 206 is
drivingly engaged with an output of the hybrid transmission 204.
The hybrid drivetrain 200 is similar to the hybrid drivetrain 100
shown in FIG. 1, with the exception that the hybrid drivetrain 200
shown in FIG. 2 does not include the primary clutch 108. The clutch
216 facilitates disengaging the gear box 218 from the first motor
generator 212.
[0033] FIG. 3 is a schematic style view of a hybrid drivetrain 300
according to another embodiment of the invention. The hybrid
drivetrain 300 includes a power source 302, a hybrid transmission
304, and a tandem axle drive unit 306, the tandem axle drive unit
306 including a first axle drive unit 344 and a second axle drive
unit 346. The power source 302 is drivingly engaged with an input
of the hybrid transmission 304. The tandem axle drive unit 306 is
drivingly engaged with an output of the hybrid transmission 304.
The hybrid drivetrain 300 is similar to the hybrid drivetrain 100
shown in FIG. 1, with the exception that the hybrid drivetrain 300
shown in FIG. 3 does not include the secondary clutch 116.
[0034] FIG. 4 is a schematic style view of a hybrid drivetrain 400
according to another embodiment of the invention. The hybrid
drivetrain 400 includes a power source 402, a hybrid transmission
404, and a motorized tandem axle drive unit 438, the motorized
tandem axle drive unit 438 including a first axle drive unit 444
and a second axle drive unit 446. The power source 402 is drivingly
engaged with an input of the hybrid transmission 404. The motorized
tandem axle drive unit 438 is drivingly engaged with an output of
the hybrid transmission 404. The hybrid drivetrain is similar to
the hybrid drivetrain 100 shown in FIG. 1, with the exception that
the hybrid drivetrain shown in FIG. 4 does not include the
secondary clutch 116 and includes the motorized tandem axle drive
unit 438.
[0035] The motorized tandem axle drive unit 438 is drivingly
engaged with a gear box 418, a first axle 430, and a second axle
432. Unlike the tandem axle drive unit 106 shown in FIG. 1, the
motorized tandem axle drive unit 438 includes a third motor
generator 440 in driving engagement therewith. Further, it is
understood that the third motor generator 440, or any other motor
generator described herein, may include a power inverter 442,
integrated therewith to facilitate a conversion of electrical power
needed to operate the third motor generator 440. The third motor
generator 440 is in electrical communication with the controller
426 and the battery 428. It is understood that the third motor
generator 440, or any of the other motor generators described
herein, may be incorporated into a gearbox, transmission, or other
driveline component of the hybrid drivetrain 400. The motorized
tandem axle drive unit 438 is configured to be placed in two modes
of operation, depending on a position of a selection clutch 434. In
a first mode of operation, the motorized tandem axle drive unit 438
operates in a high torque, dual axle mode operation, and the third
motor generator 440 may apply a driving force to propel or retard a
portion of the hybrid drivetrain 400 it is drivingly engaged with.
In a second mode of operation, the motorized tandem axle drive unit
438 operates in a low torque, single axle mode operation.
[0036] FIG. 5 is a schematic style view of a hybrid drivetrain 500
according to another embodiment of the invention. The hybrid
drivetrain includes a power source 502, a hybrid transmission 504,
and a tandem axle unit 506, the tandem axle unit 506 including a
first axle drive unit 544 and a second axle drive unit 546. The
power source 502 is drivingly engaged with an input of the hybrid
transmission 504. The first axle drive unit 544 is drivingly
engaged with an output of the hybrid transmission 504. The second
axle drive unit 546 is in electrical communication with a
controller 526 and a battery 528 of the hybrid drivetrain 500. The
hybrid drivetrain 500 is similar to the hybrid drivetrain 100 shown
in FIG. 1, with the exception that the hybrid drivetrain shown in
FIG. 5 includes the first axle drive unit 544 and the second axle
drive unit 546.
[0037] The first axle drive unit 544 is drivingly engaged with a
gear box 518 and a first axle 530 of the hybrid drivetrain 500. The
first axle drive unit 544 is conventional and well known in the art
and comprises a drive pinion, a ring gear, and differential
assembly.
[0038] The second axle drive unit 546 includes a third motor
generator 548 and is drivingly engaged with a second axle 532 of
the hybrid drivetrain. The third motor generator 548 is in
electrical communication with the controller 526 and the battery
528. It is understood that the third motor generator 548, or any of
the other motor generators described herein, may be incorporated
into a gearbox, transmission, or other driveline component of the
hybrid drivetrain 500. The third motor generator 548 may apply a
driving force to propel or retard the second axle drive unit 546 of
the hybrid drivetrain 500 through a countershaft gear assembly 550
and second axle 532, for example. Further, it is understood that
the third motor generator 548, or any other motor generator
described herein, may include a power inverter 552, integrated
therewith to facilitate a conversion of electrical power needed to
operate the third motor generator 548.
[0039] FIG. 6 is a schematic style view of a hybrid drivetrain 600
according to another embodiment of the invention. The hybrid
drivetrain 600 includes a power source 602, a hybrid transmission
604, and a tandem axle unit 606, the tandem axle unit 606 including
a first axle drive unit 644 and a second axle drive unit 646. The
power source 602 is drivingly engaged with an input of the hybrid
transmission 604. The first axle drive unit 644 is drivingly
engaged with an output of the hybrid transmission 604.
[0040] The hybrid transmission 604 includes a primary clutch 610, a
first motor-generator 612, and a gear box 614. A portion of the
primary clutch 610 acts as the input for the hybrid transmission
604. A portion of the gear box 614 acts as the output for the
hybrid transmission 604.
[0041] The first motor generator 612 is in driving engagement with
the primary clutch 610 and the gear box 614. The first motor
generator 612 is in electrical communication with a controller 616
and a battery 618. It is understood that the first motor generator
612, or any of the other motor generators described herein, may be
incorporated into a gearbox, transmission, or other driveline
component of the hybrid drivetrain 600. Depending on an electrical
control of the first motor generator 612 using the controller 616,
the first motor generator 612 may apply a driving force to propel
or retard a portion of the hybrid drivetrain 600 it is drivingly
engaged with.
[0042] The first axle drive unit 644 is drivingly engaged with the
gear box 614 and a first axle 620 of the hybrid drivetrain 600. The
first axle drive unit 644 is conventional and well known in the
art.
[0043] The second axle drive unit 646 includes a second motor
generator 622 and is drivingly engaged with a second axle 624 of
the hybrid drivetrain 600. The second motor generator 622 is in
electrical communication with the controller 616 and the battery
618. It is understood that the second motor generator 622, or any
of the other motor generators described herein, may be incorporated
into a gearbox, transmission, or other driveline component of the
hybrid drivetrain 600. The second motor generator 622 may apply
force to propel or retard the second axle 624 of the hybrid
drivetrain 600. As shown in FIG. 6, the hybrid driveline includes
as optional axle disconnect clutch 626. The hybrid drivetrain 600
is a parallel hybrid drivetrain, and may be operated in a plurality
of operating modes as described hereinbelow. The second motor
generator 622 may also include additional components to facilitate
operation and increased functionality of the second motor generator
622, such as but not limited to, an inverter 630, power electronics
for control of the second motor generator 622, a DC-DC converter,
or electronics used for a generator function. It is also understood
that second motor generator 622 may include at least a portion of a
cooling system used for electrical components.
[0044] In use, the hybrid drivetrain 600 may be operated in a
plurality of operating modes. The hybrid drivetrain 600 may be
operated in an all-electric mode, a hybrid mode, a
regeneration/braking mode, a charging mode, and a direct drive
mode. Further, it is understood that the operating modes described
hereinbelow with respect to the hybrid drivetrain 600 may be
adapted for use with the other hybrid drivetrains described herein,
utilizing the architecture of each to operate in the all-electric
mode (where applicable), the hybrid mode, the regeneration/braking
mode, the charging mode, and the direct drive mode.
[0045] In the all-electric mode, the primary clutch 610 is placed
in a disengaged position, and the battery 618 serves as the only
power source for the hybrid drivetrain 600 for the vehicle. In the
all-electric mode, the hybrid transmission 604, the second motor
generator 622, or both the hybrid transmission 604 and second motor
generator 622 may apply force to the hybrid drivetrain 600, causing
rotation of at least one of a plurality of wheel assemblies 628,
propelling the vehicle. When only the hybrid transmission 604 is
used in the all-electric mode, the axle disconnect clutch 626 may
be placed in a disengaged position, and the first motor-generator
612 of the hybrid transmission 604, in response to communication
with the controller 616, applies force to the hybrid drivetrain 600
to propel the vehicle. When only the second motor generator 622 is
used in the all-electric mode, the primary clutch 610 is placed in
a disengaged position, and the second motor generator 622, in
response to communication with the controller 616, applies a
driving force to propel the hybrid drivetrain 600 through the
second axle 624. When both the hybrid transmission 604 and the
second motor generator 622 are used in the all-electric mode, the
primary clutch 610 and the axle disconnect clutch 626 are placed in
an engaged position and the hybrid transmission 604 and the second
motor generator 622, in response to communication with the
controller 616, apply force to the hybrid drivetrain 600 to propel
the vehicle.
[0046] In the hybrid mode, the primary clutch 610 is placed in an
engaged position, and the battery 618 and the power source 602
serve as a combined power source for the hybrid drivetrain 600 for
the vehicle. In the hybrid mode, the hybrid transmission 604, the
second motor generator 622, or both the hybrid transmission 604 and
the second motor generator 622, in addition to the power source
602, may apply a driving force to the hybrid drivetrain 600 to
propel the vehicle. When the hybrid transmission 604 and the second
motor generator 622 are used in the hybrid mode, the primary clutch
610 and the axle disconnect clutch 626 are placed in an engaged
position, and the hybrid transmission 604, the second motor
generator 622, and the power source 602, in response to
communication with the controller 616, apply force to the hybrid
drivetrain 600 to propel the vehicle. When the hybrid transmission
604 is used in the hybrid mode, the primary clutch 610 is placed in
an engaged position and the axle disconnect clutch 626 is placed in
a disengaged position, and the hybrid transmission 604 and the
power source 602 (applying a driving force through the first motor
generator 612), in response to communication with the controller
616, apply a driving force to the hybrid drivetrain 600 to propel
the vehicle. When the second motor generator 622 is used in the
hybrid mode, the primary clutch 610 and the axle disconnect clutch
626 are placed in an engaged position, and the second motor
generator 622 and the power source 602 (applying force through the
first motor generator 612), in response to communication with the
controller 616, apply a driving force to the hybrid drivetrain 600
to propel the vehicle.
[0047] In the regeneration/braking mode, the hybrid transmission
604, the second motor generator 622, or both the hybrid
transmission 604 and the second motor generator 622 are used to
retard the hybrid drivetrain 600 for the vehicle to facilitate
capturing kinetic energy of the vehicle as electrical power to be
stored in the battery 618. The regeneration/braking mode may be
used to assist a conventional braking system or may be used to
regulate a speed of the vehicle when descending an incline. When
the second motor generator 622 is used in the regeneration/braking
mode, the axle disconnect clutch 626 is placed in an engaged
position and the primary clutch 610 may be placed in a disengaged
condition (it is understood that engine braking using the power
source 602 may or may not be used in addition to the
regeneration/braking mode), and the second motor generator 622
retards the hybrid drivetrain 600 to capture kinetic energy as
electrical power. When the hybrid transmission 604 is used in the
regeneration/braking mode, the axle disconnect clutch 626 may be
placed in a disengaged position and the primary clutch 610 may be
placed in a disengaged condition (it is understood that engine
braking using the power source 602 may or may not be used in
addition to the regeneration/braking mode), and the hybrid
transmission 604 retards the hybrid drivetrain 600 to capture
kinetic energy as electrical power. When both the hybrid
transmission 604 and the second motor generator 622 are used in the
regeneration/braking mode, the axle disconnect clutch 626 is placed
in a disengaged position and the primary clutch 610 may be placed
in a disengaged condition (it is understood that engine braking
using the power source 602 may or may not be used in addition to
the regeneration/braking mode), and both the hybrid transmission
604 and the second motor generator 622 retard the hybrid drivetrain
600 to capture kinetic energy as electrical power.
[0048] In the charging mode, the power source 602 and the first
motor generator 612 or the second motor generator 622 are used to
charge the battery 618. It is understood that the charging mode may
be utilized when the hybrid transmission 604 is propelling the
vehicle in the direct drive mode. In the charging mode, the axle
disconnect clutch 626 may be placed in a disengaged position and
the primary clutch 610 is placed in an engaged condition, allowing
the power source 602 and the first motor generator 612 to charge
the battery 618 while the hybrid transmission 604 is used to propel
the vehicle, if desired.
[0049] In the direct drive mode, neither the first motor generator
612 nor the second motor generator 622 are used to propel the
vehicle. It is understood that the direct drive mode may be
utilized when a charge level of the battery 618 does not permit
operation in the all-electric or hybrid modes. In the direct drive
mode, the primary clutch 610 is placed in an engaged position, and
the power source 602 in response to communication with the
controller 616, applies force (through the first motor generator
612 and the hybrid transmission 604) to the hybrid drivetrain 600
to propel the vehicle.
[0050] FIG. 7 is a schematic style view of a hybrid drivetrain 700
according to another embodiment of the invention. The hybrid
drivetrain 700 includes a power source 702, a transmission 704, and
a hybrid tandem axle drive unit 706, the hybrid tandem axle drive
unit 706 including a first axle drive unit 718 and a second axle
drive unit 720. The power source 702 is drivingly engaged with an
input of the transmission 704. The hybrid tandem axle drive unit
706 is drivingly engaged with an output of the transmission 704
through a Cardan shaft 708, for example.
[0051] The power source 702 is an internal combustion engine,
however, it is understood that the power source 702 may also be a
hybrid type power source incorporating a secondary power source in
addition to an internal combustion engine. Further, it is
understood that the power source 702 may also be a source of
electrical power, such as a fuel cell.
[0052] The transmission 704 includes at least a primary clutch 710
and a gear arrangement 712; however, it is understood that the
primary clutch 710 may form a portion of the gear arrangement 712
or that the primary clutch 710 is a separate component from the
gear arrangement 712 and drivingly engaged there with in any
conventional manner. A portion of the primary clutch 710 acts as
the input for the transmission 704. A portion of the gear
arrangement 712 acts as the output for the transmission 704. The
primary clutch 710 is a clutch which can be variably engaged, such
as a plate or cone style clutch. The gear arrangement 712 forms a
multi-speed gearbox in driving engagement with a portion of the
primary clutch 710 and the hybrid tandem axle drive unit 706. The
gear arrangement 712 may be manually or automatically operated.
[0053] The hybrid tandem axle drive unit 706 is drivingly engaged
with the transmission 704 through the Cardan shaft 708; however, it
is understood that certain embodiments of the invention may not
require the Cardan shaft 708. The hybrid tandem axle drive unit 706
comprises a motor-generator 714, a planetary drive unit 716, a
first axle drive assembly 718, and a second axle drive assembly
720. The hybrid tandem axle drive unit 706 is configured to be
placed in at least two modes of operation, depending on a position
of a selection clutch 722 of the planetary drive unit 716. In a
first mode of operation, the hybrid tandem axle drive unit 706
operates in a high torque, dual axle mode operation. In a second
mode of operation, the hybrid tandem axle drive unit 706 operates
in a low torque, single axle mode operation. As shown in FIG. 7,
the hybrid driveline 700 includes as optional an axle disconnect
clutch 724 forming a portion of the second axle drive assembly
720.
[0054] The motor-generator 714 is in driving engagement with the
transmission 704 through the Cardan shaft 708 and the planetary
drive unit 716. The motor-generator 714 is in electrical
communication with a controller 726 and a battery 728. It is
understood that the third motor-generator 714, or any of the other
motor generators described herein, may be incorporated into a
gearbox, transmission, or other driveline component of the hybrid
drivetrain 700. Depending on an electrical control of the
motor-generator 714 using the controller 726, the motor-generator
714 may apply force to or retard the portion of the hybrid
drivetrain 700 it is drivingly engaged with. The motor-generator
714 may also include additional components to facilitate operation
and increased functionality of the motor-generator 714, such as but
not limited to, an inverter, power electronics for control of the
motor-generator 714, a DC-DC converter, or electronics used for a
generator function. It is also understood that the motor-generator
714 may include at least a portion of a cooling system used for
electrical components.
[0055] The controller 726 is in electrical communication with at
least the motor-generator 714 and the battery 728. The controller
726 may be a hybrid supervisory controller with dual range
disconnect control management. It is understood that the controller
726 may also be in communication with at least one of the power
source 702, the primary clutch 710, the planetary drive unit 716,
the axle disconnect clutch 724 of the hybrid tandem axle drive unit
706, a vehicle controller (not shown), the gear arrangement 712, an
engine controller (not shown), a braking controller (not shown),
another type of controller, an advanced driver assistance system
(ADAS), or an automated driving controller. The controller 726
controls an operating mode of the hybrid tandem axle drive 706 unit
by at least controlling engagement of the primary clutch 710, by
communicating with a transmission controller (not shown) to adjust
an operating range of the gear arrangement 712, by controlling the
axle mode, by adjusting a position of the selection clutch 722 of
the planetary drive unit 716, by controlling the motor-generator
714, and by adjusting a position of the axle disconnect clutch 724
to apply a driving force to propel or retard portions of the hybrid
drivetrain 700 each are respectively drivingly engaged with.
[0056] The battery 728 is a rechargeable, electrochemical energy
storage device in electrical communication with the controller 726
and the motor-generator 714. It is understood that the battery 728
may also be in electrical communication with other components of
the hybrid drivetrain 700 or the vehicle to supply power thereto.
Further, it is understood that the battery 728 may also be another
type of electrical storage, such as an supercapacitor. In response
to the controller 726 adjusting an operating mode of the hybrid
drivetrain 700, the battery 728 may be charged or discharged. It is
also understood that the battery 728 may include at least a portion
of a cooling system used for electrical components.
[0057] The planetary drive unit 716 includes an input shaft 732, a
plurality of driving pinions 734, a transfer shaft 736, a second
output gear 738, a first output gear 740, and the selection clutch
722. Preferably, the components 732, 734, 736, 738, 740, 722 are
formed from a hardened steel, however the components 732, 734, 736,
738, 740, 722 may be formed from any other rigid material. As
shown, the planetary drive unit 716 includes the six components
732, 734, 736, 738, 740, 722 disposed in a housing 741 but it is
understood the planetary drive unit 716 may include fewer or more
components. In response to a signal sent by the controller 726, an
actuator 742 adjusts a position of the selection clutch 722.
[0058] The input shaft 732 is at least partially disposed in a
housing (not shown). Preferably, the input shaft 732 is an elongate
member, however the input shaft 732 may be any other shape.
Bearings (not shown) disposed between the input shaft 732 and the
housing permit the input shaft 732 to rotate about an axis of the
input shaft 732. The input shaft 732 has a first end portion
drivingly engaged with the motor-generator 714 and a second end
portion having a pinion carrier 746, a first set of clutch gear
teeth 748, and an engagement portion 750 formed thereon. The second
end portion is a substantially hollow body having a diameter
greater than a diameter of the first end portion. The second end
portion is drivingly coupled to the input shaft 732. Alternately,
the second end portion may be integrally formed with the input
shaft 732.
[0059] The pinion carrier 746 is a substantially disc shaped body
drivingly coupled to the second end portion of the input shaft 732.
The pinion carrier 746 includes a plurality of pinion supports 752
protruding from a first side of the pinion carrier 746 into the
second end portion of the input shaft 732. The engagement portion
750 is formed on a second side of the pinion carrier 746. As is
known in the art, the pinion carrier 746 is also known as a planet
carrier.
[0060] The engagement portion 750 is a conical surface oblique to
the input shaft 732, however, the engagement portion 750 may have
any other shape. The first set of clutch gear teeth 748 are formed
on the pinion carrier 746 radially inward from the engagement
portion 750.
[0061] The plurality of driving pinions 734 are rotatably coupled
to the pinion supports 752. Each of the driving pinions 734 have
gear teeth formed on an outer surface thereof. As is known in the
art, each of the driving pinions 734 is also known as a planet
gear. Preferably, bearings are disposed between each of the driving
pinions 734 and the pinion supports 752, however, the driving
pinions 710 may be directly mounted on the pinion supports.
[0062] The transfer shaft 736 is a shaft rotatably disposed in the
housing and having an axis of rotation concurrent with the axis of
rotation of the input shaft 732. Preferably, the transfer shaft 736
is a hollow elongate cylindrical member, however the transfer shaft
736 may be any other shape. Bearings (not shown) disposed between
the transfer shaft 736 and pinion carrier 746 permit the transfer
shaft 736 to rotate about an axis of the transfer shaft 736. The
transfer shaft 736 has a first end portion having a first set of
clutch gear teeth 754 formed on an outer surface thereof, and a
second end portion having a second set of gear teeth 756 formed on
an outer surface thereof. The first end portion and the second end
portion are integrally formed with the transfer shaft 736 and may
have a diameter substantially equal to the transfer shaft 736.
Alternately, the first end portion and the second end portion may
be substantially disc shaped bodies having an outer diameter
greater than a diameter of the transfer shaft 736. The first end
portion and the second end portion may be drivingly coupled to the
transfer shaft 736. Similarly, the first set of clutch gear teeth
754 and the second set of gear teeth 756 may be formed directly in
the transfer shaft 736. As is known in the art, the second end
portion having the gear teeth 756 is known as a sun gear. The
second set of gear teeth 756 are engaged with the plurality of
driving pinions 734 and the first set of clutch gear teeth 754 are
disposed adjacent the first set of clutch gear teeth 748 of the
pinion carrier 746.
[0063] The second output gear 738 is a gear concentrically disposed
about a portion of the transfer shaft 736. The second output gear
738 has a central perforation having a diameter greater than a
diameter of the transfer shaft 736. The second output gear 738 is a
substantially disc shaped body having a first end portion, a second
end portion defining an outer diameter of the second output gear
738, and an engagement portion 758. Bearings disposed between the
second output gear 738 and the housing permit the second output
gear 738 to rotate about an axis of the second output gear 738. The
axis of the second output gear 738 is concurrent with the axis of
the input shaft 732. A first set of clutch gear teeth 760 are
formed on the first end portion adjacent the first set of clutch
gear teeth 754 of the transfer shaft 736. A second set of gear
teeth 762 are formed on the second end portion. The engagement
portion 758 is formed in the second output gear 738 intermediate
the first end portion and the second end portion. As shown, the
engagement portion 758 is a conical surface oblique to the input
shaft 732; however, the engagement portion 758 may have any other
shape.
[0064] The selection clutch 722 is concentrically disposed about
the transfer shaft 736. The selection clutch 722 includes a set of
inner clutch collar teeth 764 formed on an inner surface thereof, a
first synchronizer ring 766, and a second synchronizer ring 768.
The second synchronizer ring 768 may be a cone clutch that is used
in conjunction with a dog clutch, wherein shifting the selection
clutch 722 utilizes a torque interrupt shift. It is understood that
it is also within the scope of the invention for the selection
clutch 722 to be a dog style clutch that does not utilize
synchronizers, requiring the hybrid driveline 700 to be placed in a
non-moving state before the selection clutch 722 can be moved. The
set of inner clutch collar teeth 764 are engaged with the first set
of clutch gear teeth 754 of the transfer shaft 736. The selection
clutch 722 can be slidably moved along the axis of the input shaft
732 as directed by the controller 726 while maintaining engagement
of the inner clutch collar teeth 764 and the first set of clutch
gear teeth 754. A shift fork 770 disposed in an annular recess
formed in the selection clutch 722 moves the selection clutch 722
along the axis of the input shaft 732 into a first position, a
second position, or a neutral position. The actuator 742, which is
drivingly engaged with the shift fork 770, is engaged to position
the shift fork 770 as directed by the controller 726. Consequently,
the shift fork 770 positions the selection clutch 722 into the
first position, the second position, or the neutral position. In
the first position, the selection clutch 722 is drivingly engaged
with the first set of clutch gear teeth 754 of the transfer shaft
736 and the first set of clutch gear teeth 748 of the pinion
carrier 746. In the second position, the selection clutch 722 is
drivingly engaged with the first set of clutch gear teeth 754 of
the transfer shaft 736 and the first set of clutch gear teeth 760
of the second output gear 738. In the neutral position, the inner
clutch collar teeth 764 of the selection clutch 722 are only
drivingly engaged with the first set of clutch gear teeth 754 of
the transfer shaft 736. It is understood the selection clutch 722,
the clutch gear teeth 754, 748, 760, 764, the synchronizer rings
766, 768, and the engagement portions 750, 758 may be substituted
with any clutching device that permits selective engagement of a
driving and a driven part.
[0065] The first synchronizer ring 766 is an annular body coupled
to the selection clutch 722 adjacent the engagement portion 750 of
the pinion carrier 746. The first synchronizer ring 766 has a first
conical engagement surface. Alternately, the first synchronizer
ring 766 may have an engagement surface having any other shape. A
biasing member (not shown) is disposed between the selection clutch
722 and the first synchronizer ring 766 to urge the first
synchronizer ring 766 away from the selection clutch 722. When the
selection clutch 722 is moved from the second position into the
first position, the first conical engagement surface contacts the
engagement portion 750 of the pinion carrier 746. As the selection
clutch 722 moves towards the first set of clutch gear teeth 748 of
the input shaft 732, the biasing member is compressed while the
selection clutch 722 engages the first set of clutch gear teeth 748
of the transfer shaft 736 and before the selection clutch 722
engages the first set of clutch gear teeth 748 of the pinion
carrier 746.
[0066] The second synchronizer ring 768 is an annular body coupled
to the selection clutch 722 adjacent the first end portion of the
second output gear 738. The second synchronizer ring 768 has a
second conical engagement surface. Alternately, the second
synchronizer ring 738 may have an engagement surface having any
other shape. A biasing member (not shown) is disposed between the
selection clutch 722 and the second synchronizer ring 768 to urge
the second synchronizer ring 768 away from the selection clutch
722. When the selection clutch 722 is moved from the first position
into the second position, the second conical engagement surface
contacts the engagement portion 758 of the second output gear 738.
As the selection clutch 722 moves towards the first set of clutch
gear teeth 760 of the second output gear 738, the biasing member is
compressed while the selection clutch 722 engages the first set of
clutch gear teeth 754 of the transfer shaft 736 and before the
selection clutch 722 engages the first set of clutch gear teeth 760
of the second output gear 738.
[0067] The first output gear 740 is a gear concentrically disposed
within the second end portion of the input shaft 732. The first
output gear 740 is a substantially cup shaped body having an inner
surface having gear teeth 772 formed on. As is known in the art,
the first output gear 740 is known as a ring gear. The gear teeth
772 are engaged with the gear teeth formed on the outer surface of
each of the driving pinions 734. The first output gear 740 includes
an output shaft 774 and first axle drive pinion 776 drivingly
coupled thereto. Alternately, the first output gear 740 may be
integrally formed with the output shaft 774. The output shaft 774
is collinear with the input shaft 732. Bearings disposed between
the output shaft 774 and the housing support the output shaft 774
and permit the output shaft 774 to rotate about an axis of the
output shaft 774. The first axle drive pinion 776 is a spiral bevel
gear the facilitates driving engagement between the axle output
shaft 774 and the first axle drive assembly 718; however, it is
understood that other type of gears may be used.
[0068] The first axle drive assembly 718 includes a first
differential assembly 778 and a first drive axle 780. The first
differential assembly 778 and the first drive axle 780 are at least
partially disposed in a first axle housing (not shown). The first
differential assembly 778 is a conventional differential assembly
comprising a ring gear, differential housing, drive pinions, and
side gears as known in the art. The side gears of the first
differential assembly 778 are respectively drivingly engaged with a
first axle output shaft and the second axle output shaft of the
first drive axle 780. The ring gear of the first differential
assembly 778 is drivingly engaged with the first axle drive pinion
776 to facilitate driving engagement between the first output gear
740 and the differential assembly.
[0069] The second axle drive assembly 720 includes an inter-axle
assembly 782, a second differential assembly 784, a second drive
axle 786, and the axle disconnect clutch 724. The second
differential assembly 784, the second drive axle 786, and the axle
disconnect clutch 724 are at least partially disposed in a second
axle housing (not shown). The inter-axle assembly 782 comprises a
geared shaft 788 in driving engagement with the second output gear
738, a Cardan shaft 790 in driving engagement with the geared shaft
788, and a second axle drive pinion 792 in driving engagement with
the Cardan shaft 790. The second differential assembly 784 is a
conventional differential assembly comprising a ring gear,
differential housing, drive pinions, and side gears as known in the
art. The side gears of the second differential assembly 784 are
respectively drivingly engaged with a first axle output shaft and
the second axle output shaft of the second drive axle 786. The ring
gear of the second differential assembly 784 is drivingly engaged
with the inter-axle assembly 782 to facilitate driving engagement
between the second output gear 738 and the second differential
assembly 784. The second drive axle 786 comprises the first axle
output shaft and the second axle output shaft. One of the first
axle output shaft and the second axle output shaft may be divided
into two portions by disengaging the axle disconnect clutch 724. By
disengaging the axle disconnect clutch 724, the inter-axle assembly
782 and the second differential assembly 784 are prevented from
being back-driven when the hybrid tandem axle drive unit 706 is
placed in a single axle mode of operation.
[0070] In use, through control of the primary clutch 710, the
selection clutch 722, and the axle disconnect clutch 724, driving
and charging can occur with and without engagement with the rest of
the hybrid drivetrain 700. The hybrid drivetrain 700 is a parallel
post transmission hybrid drivetrain that allows the tandem axle
drive unit 706 to be operated in a plurality of modes, as described
hereinbelow. The motor generator 714 is placed inline in the hybrid
driveline, and can be used to power or supplement the power source
702 for boosting or to recuperate the braking energy via the hybrid
driveline 700 by applying torque to the planetary drive unit 716 or
receiving torque from the drive axles 180, 786 via the planetary
drive unit 716. The motor generator 714 provides the following
benefits: engine downsizing, efficiency improvement by operating
the power source 702 within a narrower band (allowing the motor
generator 714 to provide acceleration flexibility), reduced gearing
in the transmission 704, increased retrofitability, and increased
functionality of a two speed electrified axle that increases
performance of the hybrid driveline 700 having the motor generator
714 located in front of the planetary drive unit 716. Further, it
is understood that through the addition of the motor generator 714,
the controller 726, and the battery 728, a conventional driveline
may be retrofitted to form the hybrid drivetrain 700. It is also
understood that the hybrid drivetrain 700 may be configured to
implement techniques that improve an efficiency of the hybrid
drivetrain 700, such as, but not limited to, on-demand cylinder
deactivation of a portion of the power source 702 via fuel shut
off.
[0071] FIG. 8 is a schematic style view of a hybrid drivetrain 800
according to another embodiment of the invention. The hybrid
drivetrain 800 includes a power source 802, a transmission 804, and
a hybrid tandem axle drive unit 894, the hybrid tandem axle drive
unit 894 including a first axle drive assembly 818 and a second
axle drive assembly 820. The power source 802 is drivingly engaged
with an input of the transmission 804. The hybrid tandem axle drive
unit 894 is drivingly engaged with an output of the transmission
804 through a Cardan shaft 808, for example. The hybrid drivetrain
800 is similar to the hybrid drivetrain 700 shown in FIG. 7, with
the exception that the hybrid drivetrain 800 shown in FIG. 8
includes a variation of the hybrid tandem axle drive unit 706. The
hybrid drivetrain 800 includes a motor-generator 814 located after
a planetary drive unit 816 and provides for operation at only a
single operation speed of the hybrid drivetrain 800. The variation
of the invention shown in FIG. 8 includes similar components to the
hybrid drivetrain 700 illustrated in FIG. 7. Similar features of
the variation shown in FIG. 8 are numbered similarly in series.
Different and additional features of the variation shown in FIG. 8
can be appreciated by one skilled in the art in view of FIG. 8 and
the hybrid drivetrain 700 illustrated in FIG. 7.
[0072] The hybrid tandem axle drive unit 894 is drivingly engaged
with the transmission 804 through the Cardan shaft 808. The hybrid
tandem axle drive unit 894 comprises the planetary drive unit 816,
the motor-generator 814, the first axle drive assembly 818, and the
second axle drive assembly 820. The hybrid tandem axle drive unit
894 is configured to be placed in at least two modes of operation,
depending on a position of a selection clutch 822 of the planetary
drive unit 816. In a first mode of operation, the hybrid tandem
axle drive unit 894 operates in a high torque, dual axle mode
operation. In a second mode of operation, the hybrid tandem axle
drive unit 894 operates in a low torque, single axle mode
operation. As shown in FIG. 8, the hybrid driveline 800 includes as
optional an axle disconnect clutch 824 forming a portion of the
second axle drive assembly 820.
[0073] The motor-generator 814 is in driving engagement with the
output shaft 874 of the first output gear 840 of the planetary
drive unit 816. The motor-generator 814 is in electrical
communication with a controller 826 and a battery 828. It is
understood that the motor-generator 814, or any of the other motor
generators described herein, may be incorporated into a gearbox,
transmission, or other driveline component of the hybrid drivetrain
800. Depending on an electrical control of the motor-generator 814
using the controller 826, the motor-generator 814 may apply force
to or retard the output shaft 874 with which it is drivingly
engaged with.
[0074] FIG. 9 is a schematic style view of a hybrid drivetrain 900
according to another embodiment of the invention. The hybrid
drivetrain 900 includes a power source 902, a transmission 904, and
a hybrid tandem axle drive unit 996, the hybrid tandem axle drive
unit 996 including a first axle drive assembly 918 and a second
axle drive unit assembly 920. The power source 902 is drivingly
engaged with an input of the transmission 904. The hybrid tandem
axle drive unit 996 is drivingly engaged with an output of the
transmission 904 through a Cardan shaft 908, for example. The
hybrid drivetrain 900 is similar to the hybrid drivetrain 700 shown
in FIG. 7, with the exception that the hybrid drivetrain 900 shown
in FIG. 9 includes a variation of the hybrid tandem axle drive unit
706. The variation of the invention shown in FIG. 9 includes
similar components to the hybrid drivetrain 700 illustrated in FIG.
7. Similar features of the variation shown in FIG. 9 are numbered
similarly in series. Different and additional features of the
variation shown in FIG. 9 can be appreciated by one skilled in the
art in view of FIG. 9 and the hybrid drivetrain 700 illustrated in
FIG. 7.
[0075] The hybrid tandem axle drive unit 996 is drivingly engaged
with the transmission 904 through the Cardan shaft 908. The hybrid
tandem axle drive unit 996 comprises a planetary drive unit 916,
the first axle drive assembly 918, a motor-generator 914, and the
second axle drive assembly 920. The hybrid tandem axle drive unit
996 is configured to be placed in at least two modes of operation,
depending on a position of a selection clutch 922 of the planetary
drive unit 916. In a first mode of operation, the hybrid tandem
axle drive unit 996 operates in a high torque, dual axle mode
operation. In a second mode of operation, the hybrid tandem axle
drive unit 996 operates in a low torque, single axle mode
operation. As shown in FIG. 9, the hybrid driveline 900 includes as
optional an axle disconnect clutch 924 forming a portion of the
second axle drive assembly 920.
[0076] The motor-generator 914 is in driving engagement with a
geared shaft 988 of an inter-axle assembly 982 of the second axle
drive assembly 920. The motor-generator 914 is in electrical
communication with a controller 926 and a battery 928. It is
understood that the motor-generator 914, or any of the other motor
generators described herein, may be incorporated into a gearbox,
transmission, or other driveline component of the hybrid drivetrain
900. Depending on an electrical control of the motor-generator 914
using the controller 926, the motor-generator 914 may apply force
to or retard the geared shaft 988 with which it is drivingly
engaged with.
[0077] FIG. 10 is a schematic style view of a hybrid drivetrain
1000 according to another embodiment of the invention. The hybrid
drivetrain 1000 includes a power source 1002, a transmission 1004,
and a hybrid tandem axle drive unit 1098, the hybrid tandem axle
drive unit 1098 including a first axle drive assembly 1018 and a
second axle drive assembly 1020. The power source 1002 is drivingly
engaged with an input of the transmission 1004. The hybrid tandem
axle drive unit 1098 is drivingly engaged with an output of the
transmission 1004 through a Cardan shaft 1008, for example. The
hybrid drivetrain 1000 is similar to the hybrid drivetrain 700
shown in FIG. 7, with the exception that the hybrid drivetrain 1000
shown in FIG. 10 includes a variation of the hybrid tandem axle
drive unit 706. The variation of the invention shown in FIG. 10
includes similar components to the hybrid drivetrain 700
illustrated in FIG. 7. Similar features of the variation shown in
FIG. 10 are numbered similarly in series. Different and additional
features of the variation shown in FIG. 10 can be appreciated by
one skilled in the art in view of FIG. 10 and the hybrid drivetrain
700 illustrated in FIG. 7.
[0078] The hybrid tandem axle drive unit 1098 is drivingly engaged
with the transmission 1004 through the Cardan shaft 1008. The
hybrid tandem axle drive unit 1098 comprises a planetary drive unit
1016, the first axle drive assembly 1018, a motor-generator 1014,
and the second axle drive assembly 1020. The hybrid tandem axle
drive unit 1098 is configured to be placed in at least two modes of
operation, depending on a position of a selection clutch 1022 of
the planetary drive unit 1016. In a first mode of operation, the
hybrid tandem axle drive unit 1098 operates in a high torque, dual
axle mode operation. In a second mode of operation, the hybrid
tandem axle drive unit 1098 operates in a low torque, single axle
mode operation. As shown in FIG. 10, the hybrid driveline 1000
includes as optional an axle disconnect clutch 1024 forming a
portion of the second axle drive assembly 1020.
[0079] The motor-generator 1014 is in driving engagement with a
second axle drive pinion 1092 of an inter-axle assembly 1082 of the
second axle drive assembly 1020. The motor-generator 1014 is in
electrical communication with a controller 1026 and a battery 1028.
It is understood that the motor-generator 1014, or any of the other
motor generators described herein, may be incorporated into a
gearbox, transmission, or other driveline component of the hybrid
drivetrain 1000. Depending on an electrical control of the
motor-generator 1014 using the controller 1026, the motor-generator
1014 may apply force to or retard the second axle drive pinion 1092
with which it is drivingly engaged with.
[0080] In use, the hybrid drivetrain 700, 800, 900, 1000 may be
operated in a plurality of operating modes. The hybrid drivetrain
700, 800, 900, 1000 may be operated in an all-electric mode, a
hybrid mode, a regeneration/braking mode, a charging mode, and a
direct drive mode. Further, it is understood that the operating
modes described hereinbelow with respect to the hybrid drivetrain
700, 800, 900, 1000 may be adapted where necessary to utilize the
architecture of each to operate in the all-electric mode (where
applicable), the hybrid mode, the regeneration/braking mode, the
charging mode, and the direct drive mode.
[0081] In the all-electric mode, the primary clutch 710, 810, 910,
1010 is placed in a disengaged position, and the battery 728, 828,
928, 1028 serves as the only power source for the hybrid drivetrain
700, 800, 900, 1000 for the vehicle. In the all-electric mode, the
hybrid tandem axle drive unit 706, 894, 996, 1098, the
motor-generator 714, 814, 914, 1014, applies force to the hybrid
drivetrain hybrid drivetrain 700, 800, 900, 1000, causing rotation
of at least one of the drive axles 780, 786, 880, 886, 980, 986,
1080, 1086, depending on a position of the selection clutch 722,
822, 922, 1022 and a location of the motor-generator 714, 814, 914,
1014, propelling the vehicle. In response to communication from the
controller 726, 826, 926, 1026, the primary clutch 710, 810, 910,
1010 is disengaged and the position of the selection clutch 722,
822, 922, 1022 is determined to operate the hybrid drivetrain 700,
800, 900, 1000 in the all-electric mode.
[0082] In the hybrid mode, the primary clutch 710, 810, 910, 1010
is placed in an engaged position, and the battery 728, 828, 928,
1028 and the power source 702, 802, 902, 1002 serve as a combined
power source for the hybrid drivetrain 700, 800, 900, 1000: In the
hybrid mode, the motor-generator 714, 814, 914, 1014, in addition
to the power source 702, 802, 902, 1002, may apply force to the
hybrid drivetrain 700, 800, 900, 1000 to propel the vehicle. When
the motor-generator 714, 814, 914, 1014 and the power source 702,
802, 902, 1002 are used in the hybrid mode, the primary clutch 710,
810, 910, 1010 is placed in an engaged position, and the
motor-generator 714, 814, 914, 1014 and the power source 702, 802,
902, 1002, in response to communication with the controller 726,
826, 926, 1026, apply force to the hybrid drivetrain 700, 800, 900,
1000, causing rotation of at least one of the drive axles 780, 786,
880, 886, 980, 986, 1080, 1086, depending on a position of the
selection clutch 722, 822, 922, 1022 and a location of the
motor-generator 714, 814, 914, 1014.
[0083] In the regeneration/braking mode, the motor-generator 714,
814, 914, 1014 is used to retard the hybrid drivetrain 700, 800,
900, 1000 for the vehicle to facilitate capturing kinetic energy of
the vehicle as electrical power to be stored in the battery 728,
828, 928, 1028. The regeneration/braking mode may be used to assist
a conventional braking system or may be used to regulate a speed of
the vehicle when descending an incline. When the motor-generator
714, 814, 914, 1014 is used in the regeneration/braking mode, the
selection clutch 722, 822, 922, 1022 is placed in a position to
facilitate driving engagement between at least one of the drive
axles 780, 786, 880, 886, 980, 986, 1080, 1086 and the
motor-generator 714, 814, 914, 1014 and the primary clutch 710,
810, 910, 1010 may be placed in a disengaged condition (it is
understood that engine braking using the power source 702, 802,
902, 1002 may or may not be used in addition to the
regeneration/braking mode), and the motor-generator 714, 814, 914,
1014 retards the hybrid drivetrain 700, 800, 900, 1000 to capture
kinetic energy as electrical power.
[0084] In the charging mode, the power source 702, 802, 902, 1002
and the first motor-generator 714, 814, 914, 1014 are used to
charge the battery 728, 828, 928, 1028. It is understood that the
charging mode may be utilized when the vehicle is stationary (only
applicable to the embodiment of the invention shown in FIG. 7) or
when the power source 702, 802, 902, 1002 is propelling the vehicle
through the hybrid drivetrain 700, 800, 900, 1000. In the charging
mode, the selection clutch 722, 822, 922, 1022 is placed in a
position to facilitate driving engagement between at least one of
the drive axles 780, 786, 880, 886, 980, 986, 1080, 1086 and the
motor-generator 714, 814, 914, 1014 and the primary clutch 710,
810, 910, 1010 is placed in an engaged condition, allowing the
power source 702, 802, 902, 1002 and the motor-generator 714, 814,
914, 1014 to charge the battery 728, 828, 928, 1028.
[0085] In the direct drive mode, the motor-generator 714, 814, 914,
1014 is not used to propel the vehicle. It is understood that the
direct drive mode may be utilized when a charge level of the
battery 728, 828, 928, 1028 does not permit operation in the
all-electric or hybrid modes. In the direct drive mode, the primary
clutch 710, 810, 910, 1010 is placed in an engaged position and the
selection clutch 722, 822, 922, 1022 is placed in a position to
facilitate driving engagement between at least one of the drive
axles 780, 786, 880, 886, 980, 986, 1080, 1086 and the transmission
704, 804, 904, 1004, and the power source 702, 802, 902, 1002 in
response to communication with the controller 726, 826, 926, 1026,
applies force (motor-generator 714, 814, 914, 1014, depending on
the embodiment) to the hybrid drivetrain 700, 800, 900, 1000 to
propel the vehicle.
[0086] In accordance with the provisions of the patent statutes,
the present invention has been described in what is considered to
represent its preferred embodiments, however, it should be noted
that the invention can be practiced otherwise than as specifically
illustrated and described without departing from its scope or
spirit.
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